采用酸洗脱钙和添加矿物质的方法,运用灰熔点测定仪研究了不同赋存形态的含钙矿物及含量对褐煤灰熔融特性的影响.结果表明,有机钙在灰化过程中生成的氧化钙微晶比含钙矿物质生成的氧化钙颗粒更易于与其他矿物质作用形成玻璃体或钙长石、钙黄长石等低熔点共融物,从而导致褐煤灰熔点的下降.两种褐煤灰的灰熔点都随CaO含量的增加先降低后升高,在CaO含量为30％～35％时达到最低值.随着CaO含量的增加,霍林河煤灰在SiO2-Al2O3-CaO三元相图中由高熔点的莫来石区移动到较低熔点的钙长石和钙黄长石区,最后到达灰熔点较高的硅酸二钙区；小龙潭煤灰由钙长石到钙黄长石区,最后达到硅酸二钙区.%By the methods of acid decalcification and added minerals, the effects of different fractions in calcium mineral and its contents on lignite ash melting characteristics were investigated on the ash fusion temperature analyzer. The results show that calcium oxide micro-crystallites, which generated from ashing process of organic calcium, are more easily interact with other minerals and form glassy materials, or low melting point eutectic materials (e. g. anorthite, gehlenite) , than calcium oxide particles from the transformation of inorganic calcium minerals, and results in the drop of lignite ash melting point. Both two lignite ash melting points firstly decreased, and then increased with the increase of calcium oxide content, and when the calcium oxide content is in the range of 30%-35%, the ash melting point is the lowest. With the increase of calcium oxide content, the position of HLH ashes in SiO2-Al2O3-CaO three phase diagrams moves from high melting point mullite district to the lower melting point of anorthite and gehlenite area, finally reaches the high melting point di-calcium silicate zone, and XLT ashes move from anorthite to gehlenite to di-calcium silicate zone.
展开▼
